In the transportation industry, there is considerable impetus for the reduction of weight of vehicle components. In many cases, for example, the reductions in weight are necessary to achieve designated fuel economy standards that are becoming even more stringent. Alternative designs of many vehicle components are often considered particularly in the automotive sector as well as in other transportation industries if the resulting parts can achieve significant weight savings, and even more so when the alternative designs further provide a cost benefit.
There are many vehicle parts for which weight savings are desired. For example, in the automotive industry, interior or exterior trim components and/or structural components, such as door trims and modules, consoles, instrument panels, and storage boxes for doors, consoles, and instrument panels, e.g., glove boxes, are but a few such items. Many of these components are made from relatively low density, flexible plastic materials that can be readily molded into various 3-Dimensional shapes instead of being made from higher density, stiffer materials, such as metals and glass fiber-reinforced plastics, where forming 3-Dimensional shapes can be more challenging.
One example of a conventional vehicle component that is made from a relatively low density thermoplastic material is a one-piece, injection molded polypropylene glove box bin. The one-piece glove box bin has molded-in ribs on a rearward facing surface that are vibration welded to a plastic lid that has a Class “A” surface, and two molded-in standing side walls that are formed on a forward facing surface and that define the 3-Dimensional box shape of the bin. Unfortunately, although the polypropylene that forms the bin has a relatively low density of from about 1 to about 1.5 grams per cubic centimeter (g/cc), the bin has a relatively typical area weight (e.g. weight per unit area) of from about 2,300 to about 3,300 grams per meter2 (g/m2). This is because the bin requires a relatively thick wall stock of from about 2.5 to about 3.5 millimeter (mm) for adequate structure due to the flexibility or relatively low specific modulus (e.g. stiffness as a function of density) of the polypropylene. Moreover, packaging and shipping of the one-piece glove box bins prior to being installed in vehicles is inefficient and adds to the cost of the bins because the two standing side wails that are molded-in prevent the bins from being stacked on each other for packaging and shipping.
An attempt to resolve at least some of these problems was disclosed in U.S. Patent Application Publication No. 2006/0138183, issued to Hein et al. (hereinafter “the '183 patent application”). The '183 patent application describes a foldable sheet that is molded from a relatively low density, flexible polypropylene and that can be folded to form a glove box for mounting in a vehicle. The foldable sheet “as molded” is substantially fiat and can be efficiently stacked for packaging and shipping. Unfortunately, the foldable sheet has a relatively typical area weight because although the polypropylene has a relatively low density, it has a low specific modulus and will therefore require a relatively thick wall stock for adequate structure.
Accordingly, it is desirable to provide a foldable substrate for a motor vehicle that can be efficiently stacked for packaging and shipping to provide a cost benefit and that can be folded to form a vehicle component that has a relatively low area weight for a significant weight savings. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.